Detachable insulator for lamp leads



Oct. 4, 1932. E. w. BRADY 1,881,168

DETACHABLE INSULATOR FOR LAMP LEADS Filed July 14, 1928 Patented Oct. 4, 1932 PATENT EDMUND W. BRADY, OF NEW BRITAIN, CONNECTICUT, ASSIGNOR TO THE BRADY ELEC- TRIC & MANUFACTURING COMPANY, OF NEVJ BRITAIN, CONNECTICUT DETACHABLE INSULATOR FOB LAMP LEADS Application filed July 14,

This invention relates to detachable insu-' lator or insulator heads for so-called lamp leads or wire holders, which in their usual form are designed to be attached to a pole or other Wooden structure, and are so formed as to maintain the wire, which in the usual form, passes through an opening in the insulator, spaced at some distance from the pole or other supporting device.

In the past, such devices comprise an 1nsulator head formed of insulating material having an opening therethrough to receive the wire, and a pin or rod cemented or otherwise permanently secured to the insulator head, this pin being provided with screw threads so that the structure may be said to comprise a lag screw of considerable length, having the insulator head secured thereto.

In the use of such structures, it is necessarv when the insulator becomes broken to remove the entire device from the pole, which must then be discarded and a new wire holder or lamp lead supplied in its place. This is due to the permanent connection. between the lag screw or pin and the insulator head. Oneobiect of my invention is to provide a detachable insulator head for lamp lead wire holders, such that the head may be readily and easily attached to and detached from the lag screw.

Another object of my invention is to provide a detachable insulator head for lamp lead wire holders. so that when the insulator becomes broken it may readily be detached from the pin or lag screw and replaced by another, without removing the screw from the pole.

A still further object of the invention is to provide a detachable insulator head for devices of this character, which while it may be readily detached from the securing means, nevertheless will be firmly held in place and not liable to he accidentally detached while in use.

To these and other ends, the invention consists in the novel features and combinations of parts to be hereinafter described. and claimed.

In the accompanying drawing:

1928. Serial No. 292,709.

Fig. 1 is a side elevational view of a lamp lead embodying my invention;

Fig. 2 is an enlarged elevational view of the lamp lead shown in Fig. 1;

Fig. 3 is a transverse sectional view on line 33 of Fig. 2;

Fig. 4c is a longitudinal sectional view on line 1-4 of Fig. 2;

Fig. 5 is a partial sectional view on line 55 of Fig. 4, and

Fig. 6 is a plan view of the resilient washer employed in the construction.

To illustrate a preferred embodiment of my invention, I have shown in Fig. 1 a frag ment of a pole or other supporting device 10, to which is secured a pin 11 carrying a detachable insulator head 1:2, through an opening 13, in which is passed a wire 14 in the usual way.

As shown more especially in Fig. 2, the

pin 11 is provided at one end with screw threads 15 so that it may be secured to the pole or other structure, as is usually the case with the ordinary lag screws. Above the threaded portion, the pin 11 may have secured thereto a nut 16, so as to be provided with wrench faces by which it may be secured in place.

Instead of cementing or otherwise permanently securing the pin to the insulator head as has usually been done in the past, I provide for a detachable connection between the pin and head. To this end in the form shown, I secure to the upper end of the pin a sup-- porting member having an upper relatively broad and flat supporting surface 17 from which depend legs 18, which are brought together adjacent their lower ends 19 to surround the upper end of the pin 11. The legs may then be secured to the pin in any con venient way, for instance by the rivet 20. In the supporting surface 17 is provided an elongated slot or opening 21, shown more especially in Fig. 3, having an enlarged portion 22 intermediate its ends.

The insulator head 12 comprises the insulating member 23, through which is the opening 13 previously referred to, this member being formed in the present instance, of insulating material.

In order to provide means upon the insulator head which will, in cooperation with the opening 21 of the supporting member upon the pin, make possible the attaching and detaching of the insulator head with ease and facility, I secure to the member 23 a securing member which will project from the base of the insulating member to be received through the opening 21, and contact with the rear face of the support 17.

In the form illustrated, this member, as shown more particularly in Fig. 4, comprises a body or stem portion 24, having a base 25 extending transversely from the body portion, and is provided at its upper end with a head 26 which, while smaller than the base portion 25, nevertheless extends transversely to some extent from the body portion to form projections thereon. The insulator 23 is provided with an opening or recess 27 which extends through the lower surface thereof, and the head and a part of the body of the securing member is adapted to be received within this opening to a sufficient extent to be rigidly and firmly secured therein, with the transverse base portion and a part of the body portion or stem projecting from the lower end of the insulator.

The securing member may then be fixed in place by the opening or recess 27 being filled with cementitious material, lead or the like 28, which will also preferably be run into channels 29 formed in the insulating material and communicating with the opening 27. It will be apparent that the material 28 will firmly adhere to the insulator and owing to the fact that it overlies the projecting portions of the head 26 will fix the securing member firmly thereto.

I also provide upon the stem or body portion 24, a washer 30, which is preferably formed of a comparatively thin sheet of some resilient material and is of flat shape except that it is slightly bowed in a longitudinal direction, as shown in Fig. 4, for a purpose which will be hereinafter explained. This washer member is, as shown in Fig. 6, provided with a rectangular opening 31, which fits loosely about the stem portion 24, but which will preferably be of such a size as to connect this member non-rotatably to the stem. As shown in Fig. 6, this opening may be of sufficient length to pass over one of the pro ecting ends of the base 25, when the other edge of the opening is drawn against the ed ge of the stem. 24, so that this member may be mounted upon the securing member after the latter has been secured to the insulator. The opening 31 may, of course, be made only large enough to pass over the head 26, in which case it must be placed upon the stem 24 before the latter is secured in place.

prevent the insulator head from In orderto becoming accidentally detached from the bracket, I provide lugs or projections 32 upon the base 25, which projections are adapted to lodge in openings 33 of the supporting member 17 when the insulator head is in place, as will be hereinafter described.

The base 25 is of the proper length to pass through the slot or opening 21 when brought into registration wt-h this opening, and the stem 24 and enlarged portion 22 of the slot 21 are so formed as to permit the rotation of the stem when the latter has been passed through the slot. This will permit the head and projecting portion of the stem to be inserted through the slot 21 and the insulator head thereafter rotated through an angle of 90 so that the base is no longer in registration with the slot. In the latter position the projections or lugs 32 will enter the openings 33, so as to prevent an accidental reverse rotation of the insulator to take place.

The operation of my device is as follows. After the parts of the detachable head have been assembled, it will be understood that the washer 30 is loosely held upon the stem or body portion 24 of the securing means, and that this washer is formed of spring or resilient material so that it will tend to resist being flattened 01' distorted from its bowed shape. In order to attach the insulator head to the bracket or support 17 upon the pin 11, the former is turned to such a position that the transverse base or foot member 25 will pass through the opening 21 with the projecting part of the stem member 24 entering the enlarged central portion 22 of the slot.

When inserting the securing member through the opening 21, sufficient pressure is exerted upon the insulator head to flatten out the resilient washer 30 to some extent,

so that the tendency of this washer to return to shape will draw the insulating member away from the support 17, and draw the foot or base 25 toward this support. After the member 25 has been inserted through the opening 21 to a sufficient extent, so that the lugs 32 will clear the edges of the opening on the rear face of the member 17, the insulator head is rotated through an angle of 90 in the case of the particular embodiment ii'" shown. At the end of this movement, the lugs 32 will. come into registration with the openings 33, and will be drawn outwardly into these openings by the spring washer 30, which is constantly urging the insulator head in a direction outwardly from the member 17. When the lugs are lodged in these openings, further rotation of the insulator head in either direction will be prevented until pressure has again been brought upon the insulator head to release the lugs from engagement in the openings. It will be apparent that the head will be firmly fixed in place so that its accidental displacement will be impossible, as any tendency of the g head to rotate so as to again bring the base portion 25 into registration with the slotted opening 21, will be resisted by the engagement of the lugs 32 in the openings 33, and movement of the insulator toward the supporting member 17 to effect disengagement of the lugs will be resisted by the spring washer 30.

When it is desired to detach the head from the pin 11, sufficient pressure must be exerted thereon in a direction to flatten out the spring washer 30, and to move the member 25 downwardly, as shown in Fig. 1, so that the lugs will be clear of the openings. Free rotation of the insulator head will then be permittedso as to bring the foot member 25 into registration with the slot 21, and thereafter the head may be drawn through the opening 21 in a longitudinal direction so as to detach the head from the pin.

It will be obvious that I have provided an insulator head which will be readily and easily attached to and detached from a pin or lag screw and at the same time when in place will be rigidly and firmly secured to the pin or screw so that there will be no play therebetween, or any danger of accidental displacement of the parts.

While I have shown and described some preferred embodiments of my invention, it will be understood that it is not to be limited to all of the details shown, but is capable of modification and variation within the spirit of the invention and the scope of the appended claims.

What I claim is:

1. A lag screw having wood piercing threads thereon, an insulator support secured thereto, and an insulator detachably secured to said support, said support comprising a relatively broad fiat supporting surface, legs projecting rearwardly from said surface, and said legs being brought together to embrace the end of said screw and being permanently secured thereto.

2. In an insulator support, a supporting pin having wood piercing threads at one end thereof, means providing wrench faces upon the pin above said threads and intermediate the ends of the pin, an insulator support permanently secured to the unthreaded end of the pin above the wrench faces, and an insulator detachably secured to said support, said support having a relatively broad flat supporting surface, and legs depending therefrom, said legs being brought together and bent around said pin to embrace the same.

In witness whereof, I have hereunto set my hand this 11th day of July, 1928.

EDMUND W. BRADY. 

